Manufacture of silk-like thread.



UNTTED STATES Patented January 3, 1905.

PATENT OEETEE.

RUDOLF MULLER, OF HOCHST-ON-THE-MAIN, GERMANY, ASSIGNOR TO FARBWERKE,VORM. MEISTER, LUCIUS 8: BRUNING, OF HOOHST-ON- THE-MAIN, GERMANY, ACORPORATION OF GERMANY.

MANUFACTURE OF SILK-LIKE THREAD.

SPECIFICATION forming part of Letters Patent No. 779,175, dated January3, 1905.

Application filed October 31, 1904:. Serial NO ZQQSS L.

To all whom it may concern.-

Be it known that I, RUDoLF MULLER, Ph. D., chemist, a citizen of theEmpire of Germany, residing at Hochst-on-the-Main, Germany, haveinvented certain new and useful Improvements in the Manufacture of Silk-Like Threads, of which the following is a specification.

1 have found a new process for the manu- I facture of silk-like threads,which consists in allowing ammoniacal solutions ofcellulosecupprammonium to issue through capillary tubes into solutionsof caustic alkalies. The threads thus formed are wound up, then I 5washed with acids and water, and finally dried. They are distinguishedby their solidity and brilliancy.

For the solutions of cellulose those of its hydration products mentionedin literature as cellulose hydrate and hydro-cellulose may be used, andhereinafter cellulose is meant to include all these compounds.

Alkalies do not precipitate the cellulose as such from its oupprammoniumsolutions, but 2 5 in a combination with copper. By this the presentprocess is differentiated from other known similar processes. Thethreads obtained containing copper are washed with acids. Thus thecupreous compound is decomposed and there remains a remarkably strongthread. The process is not essentially changed by first drying thethreads containing copper, washing with acids and water, and finallyredrying them. The concentration of the caustic alkaline lye used toseparate the cellulose from its solution may vary considerably. Forinstance, the separation may also be effected by a caustic-soda lye offour per cent. strength, yet 4 the thread obtained with a dilution tothis eX- tent seems to be less strong, while a strong concentration doesnot aflect its solidity.

Example: A solution of cellulose in ammoniacal cupric oxid obtained atordinary temperature and containing about five per cent.

of cellulose is allowed to issue through capillary apertures intocaustic-soda lye of about forty per cent. strength. The thread thusformed is directly wound up and washed successively with sulfuric acidof about twelve per cent. strength and water and finally dried in astretched condition.

In carrying out this process it is practical to surround the tube withthe capillary aperture with a second tube, through which thecaustic-soda lye is allowed to slowly pass the capillary aperture, bothapertures being downwardly directed. The thread formed descends and iscollected on a rotating drum. It is also preferable to carry out thewashing successively with an acid and water and finally drying on adrum, as it is already described in English specification No. 17,901 of1897, relating to threads obtained from a zinc-chlorid cellulosesolution. be obtained by an analogous process if a thin layer of thecellulose-cupprammonium solution is treated with caustic-soda lye,washed with acid and water, and finally dried.

Having now described my invention, what I claim is 1. Theherein-described process for the manufacture of silk-like threads,whichconsists in allowing ammoniacal solutions of cellulosecupprammoniumto issue through capillary tubes into caustic alkaline solutions,washing the wound-up thread thus formed successively with acids andwater and subsequently dryg 1t. 2. Silk-like threads obtained byallowing ammoniacal solutions of cellulose-cupprammonium to issuethrough capillary tubes into caustic alkaline solutions,washing thewoundup thread thus formed successively with acids and water andsubsequently drying it.

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing witnesses.

RUDOLF MULLER.

Witnesses:

ALFRED BRISBOIS, JOSEPH FLAoH.

Like threads, films may

